A rugby referee has been forced to abandon a derby game tonight after a mass brawl broke out between players from two British universities. However, an altercation near the touchline sparked a 30-man bust-up, with fans hurling pints of beer over players who tussled near the hoardings. TRENDING Stories Videos Your SayTensions flared over a high tackle, with Cardiff players throwing their hands in the air before Welsh referee Adam Jones penalised the indiscretion. Mr Jones blew his whistle eighteen times as players rushed to join the brawl. After players refused to respond to the referee's call for calm, Mr Jones said: "Okay, that's enough, boys.